The present invention relates to a developer storing container and an image forming apparatus using the developer storing container.
A developer storing container is detachably mounted to a developing device of an electrophotographic image forming apparatus for supplying a developer to the developing device. Conventionally, such a developer storing container includes an outer case and an inner case. The outer case includes a polygonal portion having a polygonal cross-section and an arc-shaped portion having an arc-shaped cross section. The inner case is provided in the arc-shaped portion of the outer case so as to be rotatable contacting an inner surface of the arc-shaped portion. The arc-shaped portion has a lower ejection opening for supplying the developer to the developing device. A seal member is fixed to the inner case, which is pressed against the inner surface of the arc-shaped portion around the lower ejection opening-to entirely seal the lower ejection opening.
When a user mounts the developer storing container to the developing device, the user holds the polygonal portion of the developer storing container, and sets the developer storing container in the developing device. Thereafter, the user operates an operation lever (disposed on an end of the inner case in the longitudinal direction) to rotate the inner case in the arc-shaped portion of the outer case so as to open the lower ejection opening. With this, the developer is supplied to the developing device via the lower ejection opening. In this state, the seal member has slid in a direction away from the lower ejection opening along the inner surface of the arc-shaped portion according to the rotation of the inner case. Such a developer storing container is disclosed in, for example, Japanese Laid-open Patent Publication No. 2001-42620 (Page 4, FIG. 2).